Schöngarth was captured by the allies at the end of the war. After investigations of his background, he was charged with the crime of murdering a downed Allied pilot (on 21 November 1944) and tried by a British Military Court in Burgsteinfurt. He was found guilty of this war crime on 11 February 1946 and sentenced to death by hanging. Schöngarth was executed by Albert Pierrepoint on 16 May 1946 at Hameln Prison.